Feature Request-Locking Layers

[Love_PaintNet]

Hi,

Im new here, and id like to ask for a Feature to lock layers in paint.net.
I read the post that talked about locking Layers and I know that Rick Brewster was asked about it, 
but i saw that in the popular Feature Requests it wasnt listed, so i figured it was ok to ask for it here.
I wanted to ask for it as i frequently use paint.net than have to redo hours of work, as i used the wrong layer, and than i have to give up and go to Krita.
And i really like paint.net, its easy to use, great Magic Wand tool to cut things out, i love it.
I also love this Amazing Community that exists here on paint.net.
How Rick Brewster developed this program on his own spare time, while working a full-time job, and that is so amazing.
And everyone else here who has given time to moderate the forums, give advice, make plug-ins, give help and advice to those who are new and lost to paint.net.
Sometimes i think the world can be so cynical and hard, and than i remember that a group of volunteers with no money gathered around a program Rick Brewster created,
And made MAgic, and Made Art.
And the world doesnt seem so bad.
So Thank you all. 

SO i guess, i want to ask, 
1)How complicated is it to install a Lock Layers Function in Paint.net, and how much time would it take?
2)How can I help, either with Donation to specifically implement the Lock Layers function, or with time to spend programming or bug-testing?
How much to donate?
3)Can i send a donation with a note? so i can say hi this is from me, i just wanted to say thanks for making paint.net so awesome.

Sincerely,
Love_PaintNet

[Love_PaintNet]

I almost forgot to Add.
Thanks Rick for getting out the Update to Version 4.2.5